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Finding the Fourth Proportional to 285.85, 428.98 and 123.65

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Solution

The fourth proportional to 285.85, 428.98 and 123.65 is: 185.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    285.85 : 428.98 = 123.65 : x
  2. Step 2: Convert to fraction form
    285.85/428.98 = 123.65/x
  3. Step 3: Cross multiply
    285.85x = 428.98 × 123.65
  4. Step 4: Simplify right side
    285.85x = 53,043.38
  5. Step 5: Solve for x
    x = 53,043.38/285.85
  6. Step 6: Final answer
    x = 185.56

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.